Typically, a web browser needs to completely download an entire image in a webpage before the resources (e.g., a client-server connection) that are used to download or render the image can be used to download or render another image on the webpage. When a webpage contains many images, there may be insufficient resources to download all the images on the webpage concurrently. As a result, the startup wait time experienced by an end-user in a browsing session may become unacceptably long on higher-latency networks, such as cellular 3G networks. Therefore, improved techniques for delivering images on a webpage would be desirable.